Wiring off the Rack

[kurio99]

In all but the hardest wind, I have been wiring off the gunnel on my RS700.  I'm 190 lbs with the rack set to the 3rd hole.  What can I do to get the maximum power out of the sail so that I can move out to the rack in lighter winds?  Have been using the vang to get the leach pretty straight and the boom at the corner of the hull, all of this while sailing close hauled.  Still feel like I'm sabotaging my sail shape.

Anything with the rig tension, cunningham, or outhaul that could give me the problems that I describe?

 

[edward mason]

Hey Kurio,  I dont know about the RS 700 --(never sailed one} but on all other boats I've sailed, using the vang bends the mast and  flattens the sail --useful for  DE-powering and also for pinching upwind as much as possible.Have you tried easing off the vang and sailing just a little freer with a deeper draft in the sail ? Should give a bit more power. Slightly looser outhall might also help. Hope this helps.

 

[Martin T]

Have you looked at the tuning guide here https://www.rs700.org/index.asp?Fleet=RS700&selection=Tuning

Might give you some pointers.

 

[JeffD]

I don't know RS700s but a couple of random ideas to check out...

Can you line up against other 700s and see how you are comparing? Sometimes there just isn't enough grunt in the wind to work with.

I would check your mast rake. With a fixed spreader rig too much aft rake will make the spreaders push the mast into a forward bend down low, coupled with loose lowers and mast compression as soon as you hop on the wire is a recipe to dump power exactly when you need it most.  

With most trap boats you need more rig tension to ensure the spreaders don't lose control of the mast bend as soon as you weight the wire (and consequently drop tension on your side stays,

 

[New2Cats]

Hi there,

I got myself a Musto Skiff last December and had been sailing a 600 for the previous 4 years. At 85 odd kg, you should be able to trapeze from the racks from about 8 knots. The most obvious thing to address is your trapeze line length. Have you got coarse adjusters? You should have light, medium and heavy wind settings on your trap lines. For power in that kind of breeze you need to crank on the lowers, easing the downhaul and outhaul. The kicker comes on as the breeze comes up. Once you're out on the racks, aim for near max kicker to stop the boat rolling to windward. 

 

[edward mason]

Question--how would maximum vang tension stop a boat from rolling to windward ? Not saying your're wrong , (I'm definitely NOT a trapeeze artist)---- just curious.

 

[New2Cats]

To be honest, I've no idea. I just know it works on both the 600 and the Musto. I always think of it like this: the kicker will stop you rolling to windward and the downhaul will stop you being blown over to leeward. 

 

[Matt D]

Question--how would maximum vang tension stop a boat from rolling to windward ? Not saying your're wrong , (I'm definitely NOT a trapeeze artist)---- just curious.

I tend to think of up to a certain point, more vang will power you up, as it closes your leach, and essentially trims your main in up high.  Having the top of your main trimmed in will allow every extra armfull of mainsheet to trim the full sail for more power, and thus prevent you from rolling in tow windward.  Above a certain point, more vang bends the rig and flattens the sail, as Edward Mason refers to.

With modern mains, more downhaul bends the rig, blading out the main, and opening the leach, allowing the top of the sail to fall off.  This will prevent you from going in to leward when overpowered, as the top of the lever arm isn't pulling, keeping your power down low, thus reducing the torque that the main exerts.

Caveat emptor - My experience is in other mordern boats, not the RS700.

 

[Mozzy Sails]

A bit of kicker will stop the leech from opening right out as you release main tension in those conditions when you're just starting to ease the main. It means your boom will travel out laterally as you ease main, changing the angle of attack of the sail, rather than boom moving skywards when you first ease. Having no kicker in these conditions can leave the sail feeling a bit 'on/off'. 

It wont categorically stop you from going in to windward though, anymore than down-haul will stop you capsizing to leeward. 

Don't pull too much kicker on, as once you start cranking the tension it will start to bend the mast and flatten the sail, depowering you. For that reason most people just snuggle up the slack in the kicker in conditions where they're trying to build power, but may still have to ease on occasion. 

In any decent breeze you shouldn't be struggling to get out on the rack though. And if you're not out on the rack, you shouldn't be easing, so not sure kicker is the problem. 

To be frank, if you're only trapezing off the rack 'in the hardest wind' it sounds like you need to bear off a little. You should be out on the rack on a 700 in about 8 knots upwind, regardless of sail controls and rig setting. 

 

[edward mason]

Hey Kurio,  I dont know about the RS 700 --(never sailed one} but on all other boats I've sailed, using the vang bends the mast and  flattens the sail --useful for  DE-powering and also for pinching upwind as much as possible.Have you tried easing off the vang and sailing just a little freer with a deeper draft in the sail ? Should give a bit more power. Slightly looser outhall might also help. Hope this helps.

 

[Table_Chairs]

Surely on any high performance skiff you should be able to get the boom pretty close to the boat's centreline.

If you have the boom sitting out over the rear corner of the hull and are struggling for power, you need to sheet in!

You should have the sheet pulled pretty tight in any sort of breeze until you get over-powered and need to ease to keep the boat flat.

If the wind is very light (less than 5kn?) you may need to ease slightly to help maintain flow over the sail, but you won't even be thinking about trapezing in these conditions.

 

[Mozzy Sails]

Surely on any high performance skiff you should be able to get the boom pretty close to the boat's centreline.

Not on an RS700. They don't have a jib to keep the flow attached around the back of the sail.  Just like any other mono sail you won't get any extra power by sheeting up to centre line.

If you're trying to build power you need to be keeping as tight as leech as possible, but not stalling it (watch leech ribon for hooking). You should be using main sheet tension to open and close the leech, squeezing on the main until the ribon gets dragged forward (indicating stall), then easing to allow the flow to re-establish.  You want just enough kicker so that when you ease that main tension the boom doesn't completely sky.

You can just see it in this video, at moments the camera catches the ribon off the second batten up, you can see it starting to hook, and each time it does the sailor eases a tad of main to keep the flow. Then he squeezes it back on to build the power. 



If you're holding leech tension with the main, even over the aft corner, and still can't get out on the wire in a decent breeze it is absolutely that you sailing too close to the wind.

 

[OutofOffice]

Agreed. Kicker on (not max to avoid hooking the sail), Cunningham off, outhaul eased and be sure not to choke out the main. Ease to attach flow and then tighten up on it gradually. Remember you can't point until you build power. Foot off!